This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 13 |
| 7 | 47 |
| 8 | 217 |
| 9 | 1041 |
| 10 | 5288 |
| 11 | 27844 |
| 12 | 150608 |
| 13 | 831229 |